(1) Field of the Invention
The present invention relates to a radio communication system, and more particularly, to a radio receiver for a base station which receives signals transmitted from a plurality of mobile stations in mobile communications.
In the present invention, characteristics of propagation channels, such as transmission quality which can be lowered by multipath fading or the like, can be collectively measured while the channels are in use, and the propagation characteristics of received waves containing a burst receive signal are simultaneously measured and analyzed so that a received wave having excellent propagation characteristics may be selected based on the result of the analysis.
(2) Description of the Related Art
Recent increase in data transmission speed requires that not only fluctuation of received power but the influence of multipath fading be given consideration in the field of mobile communications.
Among conventional methods for measuring the influence of multipath fading, a typical example is a method wherein the delay time of multiplex propagation is measured. Namely, a delay profile is measured based on the amount of delay of multiplex wave propagation and the received power.
Also, error rate such as parity is measured in order to monitor the communication system during operation.
The method of measuring the delay time of multiplex propagation, however, requires a special modulated signal for the measurement and is unable to be implemented during operation. Further, the measurement consumes much time.
As for the measurement of error rate such as parity, the measurement time is long and there occurs a delay in the determination of the transmission quality.